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Upper Power Limit Of Catback Exhaust

AlexCim

By AlexCim,
in Four Door Family & Wagoneers

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AlexCim Grand Master

AlexCim

Posted
Posted (edited)

As you all know, I have a Fujisubo Legalis R.

http://www.skylinesaustralia.com/forums/in...topic=90146&hl=

This exhaust is designed to be quiet but still nice to the ear. Ive been thinking and as my target is topping out a GCG, do you think THIS exhaust will be mega restrictive at those power levels (lets say 250awkw)????

Lets hypothetically say it is restrictive, I am not one to hate "loud" exhausts, I dont mind, as long as they are the right tone. Now, there are two options that i am thinking of doing if it is going to be too restrictive

- Get a straight pipe swaybar back, so keep the mid muffler and drop the rear one

or

- Get a new pipe between cat and swaybar made without a mid muffler

Do you think those changes would cause a great change in how the exhaust SOUNDS, not loudness, but the sound? I fear getting any type of drone, and im not sure how much "tuning" when into the exhaust to get it to sound smooth like it does now.

I would be leaning towards the mid muffler removal pipe, shouldnt be more then 250 bucks in mild steel with flanges and labour.

Anyone had experiance with a similar change in an exhaust??

PS, I remember when I turned the car on while i was changing catbacks(3-4 months ago), the car was just dumping from the dump pipe..... god did it sound good! RB...love it!

Edited by AlexCim
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https://www.sau.com.au/forums/topic/99372-upper-power-limit-of-catback-exhaust/
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Ska Grand Master

Ska

Posted
Posted

Well cant help you out with results from stagea exhausts, but have some very interesting results from changing my r33's.

I had my stock as a rock r33, (and I mean stock, not even a pod), I had it dyno'ed at 133rwkw.

Two weeks later all I did to the car was change the cat back to a HKS super dragger cat back, that is all and on the same dyno under similar weather conditions (similar temps) it ran 152 rwkw, a gain of 19rwkw just from adding it on.

That was about 3 months after owning it and caught the moddin bug, and within the next month I had added a pod, a pipe exhaust (yes it was basically a pipe from the turbo to the tip) and set the boost to 12 psi and put in a SAFC and a big cheap hybrid FMIC and ended up with around the 175rwkw mark.

But still one of the biggest jumps in power gain was changing the exhaust.

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